• Journal of Plant Biotechnology
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• v.47 no.4
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• pp.337-344
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• 2020

Plant growth-promoting microorganisms promote plant growth by supplying nutrients to roots and interacting with the intrinsic factors in plants through volatile organic compounds (VOCs). In this study, we evaluated the effect of UOS, plant growth-promoting fungi (PGPF) isolated from previous study, on the growth of Nicotiana tabacum L. var Xanthi nc. Phylogenetic analysis and GC-MS were used to identify the fungal species and the VOCs emitted by the UOS, respectively. The fresh weight of UOS-treated Nicotiana tabacum L. was 3.8 and 4.2-fold higher than that of the control groups grown in vertical and I-plates, respectively. Moreover, in the UOS-treated plants, the length of the primary root was half and the number of lateral roots were twice compared to those in control plants. The UOS was identified as Phoma sp. by studying spore and mycelial morphology and using phylogenetic analysis. GC-MS revealed that the VOC emitted by the UOS was hexamethylcyclotrisiloxane (D3). These results suggest that the UOS of Phoma sp. influences plant growth and root development through D3. We expect this UOS and its VOC, D3 to be utilized in the future to increase growth and enhance yield for other plants.

• Microbiology and Biotechnology Letters
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• v.39 no.4
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• pp.324-329
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• 2011

Eight endophytic fungal strains were isolated from the roots of Calystegia soldanella from the western coast of South Korea. The culture filtrate of the eight endophytic fungi were applied to waito-c rice seedlings in order to verify potential plant growth promotion activities. The results of bioassay indicated that the Cs-9-7 fungal strain possessed the highest plant growth promotion activity. Fungal culture filtrates were analyzed to verify secondary metabolites using gas chromatography and mass spectroscopy with selected ion monitoring (GC/MS-SIM). The culture filtrate of the Cs-9-7 fungal strain was confirmed to contain gibberellins GA3 (1.229 ng/mL), GA4 (3.535 ng/mL), GA7 (1.408 ng/mL) and GA12 (0.378 ng/mL). Polymerase chain reactions (PCR) were performed so as to determine the internal transcribed spacer (ITS) regions for the identification of isolated strains with universal primers ITS-1 and ITS-4. The Cs-9-7 fungal strain, isolated from the root of C. soldanella, has been named Aspergillus tubingensis Cs-9-7.

• Korean Journal of Clinical Laboratory Science
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• v.52 no.3
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• pp.229-236
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• 2020

Sixty-five molds isolated from clinical specimens were included in this study. All the isolates were molds that could be identified morphologically, strains that are difficult to identify because of morphological similarities, and strains that require species-level identification. PCR and direct sequencing were performed to target the internal transcribed spacer (ITS) region, the D1/D2 region, and the β-tubulin gene. Comparative sequence analysis using the GenBank database was performed using the basic local alignment search tool (BLAST) algorithm. The fungi identified morphologically to the genus level were 67%. Sequencing analysis was performed on 62 genera and species level of the 65 strains. Discrepancies were 14 (21.5%) of the 65 strains between the results of phenotypic and molecular identification. B. dermatitidis, T. marneffei, and G. argillacea were identified for the first time in Korea using the DNA sequencing method. Morphological identification is a very useful method in terms of the reporting time and costs in cases of frequently isolated and rapid growth, such as Aspergillus. When molecular methods are employed, the cost and clinical significance should be considered. On the other hand, the molecular identification of molds can provide fast and accurate results.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.2
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• pp.262-266
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• 1983

Influence of fungi living on the endocarp surface of depulped seeds of Panax ginseng on the dehiscence was investigated with a fungicidal treatment of the seeds and sterilization of the sand at the beginning of stratification. 1. Isolation frequency of the fungi living on the endocarp surface of de-pulped seed was reduced and hardness of the endocarp did not change significantly in seed treated with a fungicide Captan wp. 50%. A significant negative correlation $(r=-0.984^**)$ was found between the frequency of fungi isolation and the hardness of the endocarp. 2. Increase of water content in the seed treated with the fungicide was delayed 20days compared to the untreated. 3. Growth of the embryo and dehiscence of the seed was suppressed by the fungicide treatment. The length of the embryo was inversely proportional to the hardness of the seed. It is suggested that the fungi facilitate the softening of the endocarp thereby enhancing the supply of oxygen and water necessary for the embryo development, therefore, accelerate the growing of embryo and cause the dehiscence.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.60-60
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• 1993

새로운 항생물질을 개발하기 위하여 토양으로부터 분리한 균주를 액체배지에서 배양하여 그 배양액을 여러 검정균에 대하여 종이디스크법으로 항균효력을 측정하였다. 그 결과 G(＋), G(－)균에 강한 항균효력을 보인 토양균 SNUS 9101-55와 C. aibicans와 같은 진균류에 항균력을 보인 토양균 SN-US 9101-68을 선택하여 각각의 배양액에서 항생물질을 분리하고, 분리한 항생물질의 구조를 규명하고자 하였다. 토양균 SNUS 9101-55의 배양액으로부터 항생물질을 분리하기 위하여 양이온 교환수지 관 크로마토그래피와 셀룰로오스 관 크로마토그래피를 수행하여 시료 AMJ-I-212-B를 얻었다. 시료 AMJ-I-212-B의 IR, $^1$H-NMR, FAB-MS 스펙트럼을 얻어 분리한 항생물질의 구조를 분석하고 Sakaguchi test와 같은 정색반응을 통하여 그 발색단을 동정하여 이 항생물질의 구조가 스트렙토마이신과 동일하다는 것을 확인하였다.

• Korean journal of applied entomology
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• v.18 no.4 s.41
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• pp.161-167
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• 1979

The study has been carried to investigate a possibility to control several major insect pest of forest by microbial pathogens existing in nature as one of the biological control measure. Microorganisms including polyhedral virus isolated from diseased fall webworm were total of 4 kinds pathogenic microbes among these 4 kinds were polyhedral virus and Bacillus .species. Control effect of these two pathogens appeared to be $70.6\%$ and $49.5\%$, respectively, when they were compared with those of control plot that was $27.8\%$. Each one of bacterium species and fungus species were isolated from diseased Japanese alder leaf beetle. Pathogenisity to the healthy beetle was recognized by the fungus species, while the bacterium showed none of pathogenisity. The fungus was identified as Beauveria sp. and its effect on the beetle control was $96.2\%$ while untreated plot showed $49.2\%$ of dead beetles in the same period. Fifteen species of microbes were isolated from diseased larvae of pine gall midge. Six species out of 15 showed certain level of insecticidal effect to the larvae of the insects. The highest efficiency was showed by a fungus species, Fusarium sp. and was followed by Bacillus SP. I, Spicaria sp. pathogens isolated from larvae of pine gall midge did not affected to both of Japanese alder leaf beetles and fall webworms in any means.

• Korean Journal of Agricultural Science
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• v.26 no.1
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• pp.77-83
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• 1999

The populations of microorganisms adhered on rice straws which had been ricked in the fields around Chungchong areas during the winter season from February to March in 1998 were investigated. The number of mesophilic bacteria including bacilli was generally high in the middle part of straw. And it appeared to be higher in the samples from rural areas than those from suburb. Thermophilic bacteria and actinomycetes were rarely to be detected in most samples. Coliform bacteria were detected in a few samples which collected from Kwanpyong-dong of Taejon-city, Jangpyong-meun and Jungsan-meun of Chongyang-koon, indicating that these areas were contaminated by sewage and livestock wastes. Following the fermentation of Chungkukgang employed the middle parts of straws from Mok-meun of Chongyang-koon as a source of microbial inoculum, qualities of the fermented products such as amino-nitrogen content, viscosity and protease activity, were examined: the application of rice straws resulted in better qualities of the fermented products when compared to the control, however the methods of application appeared to have little or no effect on the quality.

• Korean Journal of Agricultural Science
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• v.12 no.2
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• pp.199-205
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• 1985

1. Alternaria tenuis, Cladosporium cladosporioides, Curvularia lunata Fusarium semitectum, Gerlachia oryzae, Phoma sp. Trichoconiella padwickii were found associated with ear blighting of rice plants. The frequency of isolation of the fungi was found to be higher from the severely discolored rice grains than that from the brownish spotted grains, but H. oryzae was encounted highly from the latter. 2. Higher counts of Alternaria tenuis, Helminthosporium oryzae, Trichoconiella padwickii, Fusarium moniliforme, Fusarium semitectum were observed under alternating cycles of 12hrs of light and darkness than under complete darkness but G. oryzae was encountered highly under darkness in the blotter. While no difference in the occurrence of the other fungi was recorded under l2hr NUV light-12hr darkness cycles and darkness. 3. A. tenuis and C. cladosporioides were encountered highly at the lower temp. $(15^{\circ}C)$ but Phoma sp. was occurred highly at the higher temp. $(30^{\circ}C)$ when the seeds were incubated in the blotter. 4. Artificial inoculation of the fungi in the ears of rice plants caused severe discoloration of rice grains and reduced 1,000 grain weights and grain ripening percentage.

• The Korean Journal of Mycology
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• v.22 no.4
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• pp.366-377
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• 1994

The base composition of DNA of Aspergillus phoenicis, Rhizopus acidus and Candida albicans treated with cycloheximide and nalidixic acid during the culture was analyzed to compare with the control. The contents of base in the DNA were inhibited by cycloheximide, 20.4% of adenine, 43.1% of thymine, 40.9% of cytosine, 35.3% of guanine, 32.2% of purine, and 42.7% of pyrimidine for A. phoenicis. In R. acidus, 34.2% of adenine, 42.1% of thymine, 38.0% of cytosine, 18.1% of guanine, 24.1% of purine and 40.0% of pyrimidine were depressed by cycloheximide. In the antibiotic treatment of C. albicans, 58.3% of adenine, 58.5% of thymine, 58.1% of cytosine, 42.4% of guanine, 46.8% of purine and 58.8% of pyrimidine were inhibited to compare with the control. The nalidixic acid treatments were showed that, in A. phoenicis 41.6% of adenine, 47.1% of thymine, 59.3% of cytosine, 46.3% of guanine, 45.6% of purine and 57.2% of pyrimidine were inhibited. When R. acidus was treated with nalidixic acid, 59.1% of adenine, 54.7% of thymine, 35.3% of cytosine, 37.4% of guanine, 45.9% of purine and 44.9% of pyrimidine decreased. In treatment of nalidixic acid, the content of DNA was depressed 60.1% of adenine, 68.6% of thymine, 60.7% of cytosine, 40.0% of guanine, 45.8% of purine and 63.5% of pyrimidine for C. albicans In the DNA synthesis of three fungal cells, cycloheximide and nalidixic acid treatments were analyzed obviously that the biosynthesis of pyrimidine was depressed than that of purine. Therefore, it was showed that the DNA contents in the various fungal cells were inhibited remarkably in nalidixic acid treatment than cycloheximide.

• Food Science and Preservation
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• v.30 no.6
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• pp.1056-1071
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• 2023

This study aimed to investigate the quality and microbial population changes for 90 days under two fermentation conditions, outdoors and indoors (35℃), with starters (single or mixed) in soybean paste. Bacillus velezensis NY12-2 (S1), Debaryomyces hansenii D5-P5 (S2), Enterococcus faecium N78-11 (S3), and their mixtures (M) were used for the makjang fermentation. The content of amino-type nitrogen among the makjang samples was highly shown in the indoors, followed by M, S3, and S2. The glutamic and aspartic acid contents in the M sample fermented in the indoors showed the highest values of 867.42±77.27 and 243.20±15.79 mg/g, respectively. By the electronic tongue analysis, the M sample fermented in the indoors exhibited lower saltiness and higher umami than the others. Consequently, we expect that using mixed strains, such as Bacillus, Debaryomyces, and Enterococcus, under constant conditions showed potential to the quality improvement of soy products.